After the two sons of Aaron died (in Parshah Shemini), G‑d warns against anybody going into the special chamber of the Miskan called the Holy of Holies. Only Aaron himself may enter, once a year, on Yom Kippur, the holiest day of the year. Another thing done on Yom Kippur is that two goats are taken and a lottery is made. One goat is offered to G‑d and the second one, to "azazel", is sent to the wilderness to atone for the sins of the Jews.

Other important warnings in the Parshah of Acharie: It is forbidden to bring a korban (sacrifice), anywhere but in the Holy Temple. It is forbidden to eat blood in any way (this is why all kosher meat is salted—to take out the blood, and why we check eggs for blood before using); and a discussion of those who we are forbidden to marry.